RESUMO
UNLABELLED: Recent investigations have established the feasibility of using exogenously delivered angiogenic growth factors to increase collateral artery development in animal models of myocardial and hindlimb ischemia. OBJECTIVE: Our aim was to evaluate the ability of a stabilized form of acidic fibroblast growth factor (aFGF-S117) to stimulate collateralization and arteriogenesis in the rabbit hindlimb following the surgical induction of ischemia by femoral artery extraction. A secondary objective was to examine angiogenic and arteriogenic effects of aFGF-S117 in the absence of a peripheral blood flow deficit. METHODS AND RESULTS: Five days after femoral artery removal, aFGF-S117 (1, 3, or 30 microg/kg) was intramuscularly delivered into the hindlimb, three times per week for 2 consecutive weeks. End-point measurements performed on day 20 found that hindlimb reserve blood flow was significantly improved in rabbits that received 3 or 30 microg/kg of aFGF-S117, with no difference in efficacy between these two doses. These hemodynamic results were supported by angiographic evidence showing enhanced density of collateral vessels in the medial thigh region and histological findings of increased capillary density within the gastrocnemius muscle from rabbits treated with aFGF-S117. When an efficacious dose of 3 microg/kg of aFGF-S117 was administered to sham-operated rabbits with intact femoral arteries, there was no change in any of the blood flow, angiographic or histological parameters measured. CONCLUSIONS: These findings demonstrate that a stabilized form of aFGF stimulated the development of functional collateral arteries in the rabbit hindlimb, an effect which was dependent upon removal of the femoral artery. These results suggest that aFGF-S117 may have therapeutic potential for the treatment of arterial occlusive disorders.
Assuntos
Circulação Colateral , Fator 1 de Crescimento de Fibroblastos/farmacologia , Membro Posterior/irrigação sanguínea , Isquemia/fisiopatologia , Animais , Arteriopatias Oclusivas/tratamento farmacológico , Arteriopatias Oclusivas/fisiopatologia , Artérias , Capilares , Artéria Femoral/cirurgia , Masculino , Modelos Animais , Neovascularização Fisiológica , Coelhos , Fluxo Sanguíneo Regional , Estimulação QuímicaRESUMO
Small molecule inhibitors of KDR kinase activity have typically possessed poor intrinsic physical properties including low aqueous solubility and high lipophilicity. These features have often conferred limited cell permeability manifested in low levels of cell-based KDR inhibitory activity and oral bioavailability. Thus, the design of inhibitors with appropriate physical properties has played a critical role in the development of clinical candidates. We present a variety of structural modifications that have afforded improvements in physical properties and thereby have addressed suboptimal cellular potency and pharmacokinetics for three unique classes of KDR kinase inhibitors.
Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Sítios de Ligação , Disponibilidade Biológica , Permeabilidade da Membrana Celular , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Modelos Moleculares , Estrutura Molecular , Solubilidade , Relação Estrutura-Atividade , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/químicaRESUMO
A series of N-(1,3-thiazol-2-yl)pyridin-2-amine KDR kinase inhibitors have been developed that possess optimal properties. Compounds have been discovered that exhibit excellent in vivo potency. The particular challenges of overcoming hERG binding activity and QTc increases in vivo in addition to achieving good pharmacokinetics have been acomplished by discovering a unique class of amine substituents. These compounds have a favorable kinase selectivity profile that can be accentuated with appropriate substitution.
Assuntos
Aminopiridinas/síntese química , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Piridinas/síntese química , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Tiazóis/síntese química , Administração Oral , Aminopiridinas/farmacocinética , Aminopiridinas/farmacologia , Animais , Disponibilidade Biológica , Linhagem Celular , Cães , Canal de Potássio ERG1 , Eletrocardiografia/efeitos dos fármacos , Canais de Potássio Éter-A-Go-Go , Técnicas In Vitro , Pulmão/enzimologia , Macaca mulatta , Masculino , Camundongos , Microssomos Hepáticos/metabolismo , Fosforilação , Piridinas/farmacocinética , Piridinas/farmacologia , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Tiazóis/farmacocinética , Tiazóis/farmacologia , Distribuição Tecidual , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
PURPOSE: To test the hypothesis that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) provides a useful in vivo measure of passive blood retinal barrier permeability surface area product (BRB PS) in experimental diabetic retinopathy. METHODS: BRB PS (cm(3)/min) was measured using DCE-MRI and Gd-DTPA (MW 590 Da) in urethane-anesthetized control rats, sodium iodate-treated rats, rats receiving intravitreally injected human serum albumin (HSA) or vascular endothelial growth factor/vascular permeability factor (VEGF/VPF), or in rats that were diabetic for 2, 4, 6, or 8 months. RESULTS: Sodium iodate-treated rats exhibited an eightfold increase (P < 0.05) in BRB PS compared to that in control animals. Furthermore, in iodate-treated rats, the average vitreous signal enhancement was linearly dependent on Gd-DTPA dose (r = 0.91, P < 0.0001). Six hours postinjection, VEGF/VPF-treated rats exhibited a threefold increase in BRB PS (P < 0.05) compared to eyes injected with HSA. In 2-, 4-, and 6-month diabetic rats, BRB PS was not significantly different (P > 0.05) from control BRB PS values. After 8 months of diabetes, a twofold increase (P < 0.05) in PS over control PS values was found. DCE-MRI demonstrated that the BRB becomes leaky immediately before death, possibly causing an artificial increase in retinal permeability in methods that require enucleation or retinal isolation to assess permeability. CONCLUSIONS: DCE-MRI provides a sensitive, noninvasive, and linear assay that accurately measures, without potential artifacts associated with death and enucleation, passive BRB PS in experimental diabetes. DCE-MRI BRB PS measurements are expected to provide a useful surrogate marker of drug treatment efficacy.
Assuntos
Barreira Hematorretiniana , Diabetes Mellitus Experimental/diagnóstico , Retinopatia Diabética/diagnóstico , Imageamento por Ressonância Magnética , Vasos Retinianos/patologia , Animais , Permeabilidade Capilar/efeitos dos fármacos , Meios de Contraste , Gadolínio DTPA , Iodatos/farmacologia , Ratos , Albumina Sérica/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologiaRESUMO
There is ample therapeutic opportunity for the use of antiangiogenic inhibitors in the clinic, as there are several human diseases that are dependent upon angiogenesis [1]. However, no disease has attracted as much attention as a target for antiangiogenic therapy as malignant disorders. There is a vast amount of literature acting as proof-of-principle for the use of angiogenic inhibitors as effective agents for blocking tumour-induced angiogenesis and subverting tumour growth and disease dissemination. One of the unique attractions of targeting tumour angiogenesis is that vascular endothelial cells are a genetically stable population in which acquisition of therapeutic resistance might be less efficient than in genetically unstable tumour cells [2,3]. This review covers inhibitors that target the tumour angiogenic agent vascular endothelial growth factor and its receptors as one such antiangiogenic approach. Many agents in this class are in clinical trials with limited reports of toxicity and some early evidence of clinical benefit.
Assuntos
Inibidores da Angiogênese/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Fatores de Crescimento Endotelial/antagonistas & inibidores , Linfocinas/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Tecnologia Farmacêutica/tendências , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Animais , Fatores de Crescimento Endotelial/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Linfocinas/fisiologia , Neovascularização Patológica/tratamento farmacológico , Receptores de Fatores de Crescimento do Endotélio Vascular/fisiologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
Pyrimidino-thiazolyl carbonitriles were prepared that are potent VEGFR-2 (KDR) kinase inhibitors. The modification of lead structures resulted in 3m which exhibited the best overall profile in KDR inhibitory activity, iv/po pharmacokinetics, and reduced hERG affinity.
Assuntos
Nitrilas/síntese química , Nitrilas/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/síntese química , Pirimidinas/farmacologia , Tiazóis/síntese química , Tiazóis/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Cães , Macaca mulatta , Estrutura Molecular , Nitrilas/química , Inibidores de Proteínas Quinases/química , Pirimidinas/química , Ratos , Sensibilidade e Especificidade , Relação Estrutura-Atividade , Tiazóis/química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
This study was designed to test the ability of adenovirus-delivered vascular endothelial growth factor (Ad-VEGF) to stimulate angiogenesis and arteriogenesis in the rabbit hindlimb following the induction of ischemia and to evaluate the functional changes in the collateral circulation. Ten days after the surgical induction of hindlimb ischemia, either a control virus (1 x 10(9) pfu) or an adenovirus containing the gene for VEGF(165) (1 x 10(6), 1 x 10(7), 1 x 10(8), or 1 x 10(9) pfu) was administered intramuscularly into the ischemic limb. Thirty days after administration of the adenoviral vectors, skeletal muscle capillary density was assessed and angiography was performed as markers of angiogenesis and arteriogenesis, respectively. Hindlimb blood flow was directly measured and hyperemic tests were performed to evaluate the functional improvements in collateral blood flow. Animals treated with Ad-VEGF at 1 x 10(8) and 1 x 10(9) pfu showed elevated levels of circulating VEGF and dose-dependent hindlimb edema. These doses also led to a robust angiogenic response (i.e., increase in capillary density), but failed to improve collateral blood flow. Consistent with the lack of a functional response, there was no angiographic evidence of enhanced arteriogenesis with any dose of Ad-VEGF. Following the induction of hindlimb ischemia, administration of Ad-VEGF stimulated capillary sprouting (i.e., angiogenesis), but did not increase the growth and development of larger conduit vessels (i.e., arteriogenesis) or improve collateral blood flow. These results support the concept that VEGF may not be expected to have therapeutic utility for the treatment of peripheral or myocardial ischemia.
Assuntos
Indutores da Angiogênese/uso terapêutico , Circulação Colateral/efeitos dos fármacos , Membro Posterior/irrigação sanguínea , Isquemia/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Adenoviridae , Angiografia , Animais , Capilares , Músculo Esquelético/irrigação sanguínea , Coelhos , Distribuição Aleatória , Proteínas Recombinantes/biossíntese , Fluxo Sanguíneo Regional , Falha de TratamentoRESUMO
An azo-dye lead was modified to a novel N-(1,3-thiazol-2-yl)pyridin-2-amine series of KDR kinase inhibitors through the use of rapid analog libraries. This new class has been found to be potent, selective, and of low molecular weight. Molecular modeling has postulated an interesting conformational preference and binding mode for these compounds in the active site of the enzyme.
Assuntos
Aminas/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Aminas/síntese química , Sítios de Ligação , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Ligação Proteica , Conformação Proteica/efeitos dos fármacos , Relação Estrutura-Atividade , Termodinâmica , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/químicaRESUMO
3,7-Diarylsubstituted imidazopyridines were designed and developed as a new class of KDR kinase inhibitors. A variety of imidazopyridines were synthesized and potent inhibitors of KDR kinase activity were identified with good aqueous solubility.
Assuntos
Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Piridinas/síntese química , Piridinas/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Desenho de Fármacos , Humanos , Estrutura Molecular , Solubilidade , Relação Estrutura-AtividadeRESUMO
1,5-Diarylbenzimidazoles have been identified as potent inhibitors of KDR kinase activity. The series was developed with a goal of finding compounds with optimal drug-like properties. This communication describes structural modifications in the series that enhance solubility, lower protein binding, and provide compounds with excellent potency and pharmacokinetic profiles.
Assuntos
Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Fenômenos Químicos , Físico-Química , Cães , Desenho de Fármacos , Inibidores Enzimáticos/farmacocinética , Meia-Vida , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Conformação Molecular , Ratos , Relação Estrutura-AtividadeRESUMO
Inflammatory breast cancer (IBC) is a specific type of breast tumor that generally has a poor prognosis, in spite of recent advances in treatment. In the present study, semiquantitative reverse transcriptase polymerase chain reaction examination of resected specimens showed that angiogenic factors, not lymphangiogenic factors, are overexpressed in IBC tumors, compared with non-IBC tumors. Immunohistochemical analysis of the specimens revealed a significantly higher population of tumor-infiltrating (TI) endothelial cells (ECs) or endothelial precursor cells (EPCs) in tumor-associated stroma of IBC specimens than in non-IBC specimens. In a previous study, we examined the phenotype of host cells in response to transplanted IBC cells, using an established human IBC xenograft model (WIBC-9) (Shirakawa et al., Cancer Res 2001;61:445-51). The data obtained in that study are consistent with the findings of the present study. To explore the therapeutic potential of blocking vascular endothelial growth factor (VEGF) and angiopoietin (Ang) pathways in IBC, established vectors encoding soluble Flt-1 (sFlt-1) and soluble Tie2 (sTie2) were injected directly into WIBC-9. Both vectors produced growth inhibition ratios of WIBC-9 that were significantly higher than those of a non-IBC xenograft (MC-5). Also, both vectors suppressed WIBC-9 lung metastases. The efficacy correlated with the number of TI ECs/EPCs, which was determined by fluorescence-activated cell sorting. These ECs/EPCs incorporated acetylated lipoprotein and were integrated within a HUVEC monolayer in vitro culture on day 5.
Assuntos
Neoplasias da Mama/metabolismo , Endotélio/metabolismo , Angiopoietina-1 , Animais , Antígenos CD34/biossíntese , Separação Celular , Células Cultivadas , Primers do DNA/metabolismo , Fatores de Crescimento Endotelial/metabolismo , Citometria de Fluxo , Vetores Genéticos , Humanos , Imuno-Histoquímica , Linfocinas/metabolismo , Glicoproteínas de Membrana/metabolismo , Camundongos , Metástase Neoplásica , Transplante de Neoplasias , Neovascularização Patológica , Fenótipo , Prognóstico , Proteínas Proto-Oncogênicas/biossíntese , Receptores Proteína Tirosina Quinases/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
We have synthesized and evaluated the activity of 3,6-disubstituted pyrazolo[1,5-a]pyrimidines as a new class of KDR kinase inhibitors. Starting with screening lead 1, potency against isolated KDR was fully optimized with 3-thienyl and 4-methoxyphenyl substituents at the 6- and 3-positions (3g, KDR IC(50)=19 nM), respectively. The synthesis and SAR of these compounds are described.
Assuntos
Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Pirazóis/síntese química , Pirazóis/farmacologia , Pirimidinas/síntese química , Pirimidinas/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fatores de Crescimento Endotelial/antagonistas & inibidores , Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Linfocinas/antagonistas & inibidores , Linfocinas/farmacologia , Mitógenos/antagonistas & inibidores , Mitógenos/farmacologia , Relação Estrutura-Atividade , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
2,4-Disubstituted pyrimidines were synthesized as a novel class of KDR kinase inhibitors. Evaluation of the SAR of the screening lead compound 1 (KDR IC(50)=105 nM, Cell IC(50)=8% inhibition at 500 nM) led to the potent 3,5-dimethylaniline derivative 2d (KDR IC(50)=6 nM, cell IC(50)=19 nM).
Assuntos
Inibidores da Angiogênese/síntese química , Pirimidinas/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Células Cultivadas , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Pirimidinas/síntese química , Relação Estrutura-AtividadeRESUMO
We have discovered 3-(5-thien-3-ylpyridin-3-yl)-1H-indoles as potent inhibitors of KDR kinase activity. This communication details the evolution of this novel class from a potent screening lead of vastly different structure with an emphasis on structural modifications that retained activity and provided improvements in key physical properties. The synthesis and in-depth evaluation of these inhibitors are described.
Assuntos
Inibidores da Angiogênese/síntese química , Indóis/síntese química , Indóis/farmacocinética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Administração Oral , Inibidores da Angiogênese/farmacocinética , Inibidores da Angiogênese/farmacologia , Animais , Disponibilidade Biológica , Linhagem Celular , Meia-Vida , Indóis/farmacologia , Concentração Inibidora 50 , Ratos , Relação Estrutura-AtividadeRESUMO
We have introduced solubilizing functionality to a 3,6-disubstituted pyrazolo[1,5-a]pyrimidine series of KDR kinase inhibitors to improve the physical properties of these compounds. The addition of a basic side-chain to the 6-aryl ring, introduction of 3-pyridyl groups, and most significantly, incorporation of a 4-pyridinonyl substituent at the 6-position of the core are modifications that maintain and often enhance the intrinsic potency of this class of inhibitors. Moreover, the improvements in physical properties result in marked increases in cellular activity and more favorable pharmacokinetics in rats. The synthesis and SAR of these compounds are described.
Assuntos
Inibidores da Angiogênese/síntese química , Pirimidinas/farmacocinética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/farmacocinética , Inibidores da Angiogênese/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Taxa de Depuração Metabólica , Farmacocinética , Pirimidinas/síntese química , Pirimidinas/farmacologia , Ratos , Solubilidade , Relação Estrutura-AtividadeRESUMO
Modifications to the basic side-chain of early lead structures of the indolyl quinolinone class of KDR kinase inhibitors resulted in improved pharmacokinetic and ancillary profiles. Specifically, compounds bearing 5-amido- and 5-sulphonamido-indolyl substituents exhibited lower plasma clearance and weaker binding affinity for the I(Kr) potassium channel hERG.